The invention relates to a piping system, and more particularly, to an active acoustic piping technique for delivering acoustical impulses into materials flowing within a pipe.
There are a number of applications that utilize acoustics in piping systems. For example, piping systems can employ acoustics for locating faults (e.g., leaks or corrosion) in the piping of a system, measuring internal dimensions of the pipes of a system, and monitoring the material flowing through a pipe.
In general, conventional systems adapted for such applications introduce pressure fluctuations into a piping system for diagnostic purposes. For example, by providing a known pressure pulse to a piping system and then measuring the pressure at a point downstream, a determination can be made as to whether the system has leaks. Typical mechanisms for producing the desired pressure fluctuations are linear actuation methods aimed down the pipe, or a number of linear actuators located about the circumference of the pipe.
However, there appears to be no piping actuation method that uses a single or multiple cylindrical actuators to operate on the fluid media flowing within a piping system. Moreover, the conventional linear actuators are typically bulky, and may not fit the form of an existing cylindrical pipe. Nor are they designed to produce acoustic power sufficient for functions such as decontamination, flow unclogging, fluid and particulate mixing, or particulate size reduction.
What is needed, therefore, are techniques for performing functions such as acoustic decontamination, flow unclogging, fluid and particulate mixing, or particulate size reduction in a piping system.
One embodiment of the present invention provides an active acoustic piping apparatus for processing flow material. The apparatus includes an inner pipe having an external perimeter and a center, and a transducer layer disposed around the inner pipe""s external perimeter. The transducer layer is adapted for receiving power from an alternating supply and providing acoustic energy. The apparatus further includes a buffer zone around the transducer layer. The buffer zone is adapted to provide an acoustic impedance mismatch, thereby concentrating acoustic energy from the transducer layer into the inner pipe""s center. The apparatus can be adapted to operate with acoustic energy on matter flowing through a piping system to perform at least one of pipe flow unclogging, fluid decontamination, fluid and particulate separation, fluid and particulate mixing, and reducing particulate size.
In one such embodiment, the external perimeter of the inner pipe is coated with an acoustic absorbing material so as to facilitate absorption of acoustic energy into the inner pipe""s center. The transducer layer and the inner pipe can be slotted in one or more locations, thereby providing a corresponding nodal region opposite each slot where heavier flow material will tend to settle. The inner pipe can have an oval shape defining a short and a long axis, and a slot on the short axis. In such an embodiment, the nodal region is wider than that of a circular pipe. Alternatively, the transducer layer and the inner pipe are slotless, thereby providing a quad nodal region.
The buffer zone around the transducer layer can be, for example, an air chamber. In one such embodiment, the apparatus further includes an outer shell disposed around the transducer layer, wherein the air chamber buffer zone is maintained between the outer shell and the transducer layer with standoffs. The outer shell has an internal surface that can be coated with an acoustic reflecting material. Alternatively, the buffer zone around the transducer layer can be a material (e.g., potting material) having an acoustic impedance that inhibits outward projection of acoustic energy.
Another embodiment of the present invention provides a method for processing flow material traveling through a piping system. The method includes flowing the flow material through an inner pipe having an external perimeter and a center, and providing acoustic energy into the pipe with a plurality of transducer elements disposed around the external perimeter of the inner pipe. The method further includes concentrating the acoustic energy into the inner pipe""s center by providing an acoustic impedance mismatch with a buffer zone around the plurality of transducer elements. The flow material can be operated on by the acoustic energy, where the method further includes at least one of pipe flow unclogging, fluid decontamination, fluid and particulate separation, fluid and particulate mixing, and reducing particulate size. In one particular embodiment, the method includes mixing the flow material by providing a plurality of out of phase nodal regions. Alternatively, the method includes separating particulates included in the flow material by providing a consistent nodal region where heavier particles settle.
Another embodiment of the present invention provides a method for manufacturing an apparatus adapted for processing flow material traveling through a piping system. The method includes providing an inner pipe having an external perimeter and a center. The method further includes disposing a plurality of transducer elements around the inner pipe. The transducer elements are adapted for providing acoustic energy. The method further includes providing a buffer zone around the plurality of transducer elements. The buffer zone is adapted for concentrating the acoustic energy into the inner pipe""s center by providing an acoustic impedance mismatch.
In one embodiment, the method further includes coating the external perimeter of the inner pipe with an acoustic absorbing material so as to facilitate the absorption of acoustic energy into the inner pipe""s center. In another embodiment, the method further includes providing a slot in the plurality of transducer elements disposed around the inner pipe, thereby enabling a corresponding nodal region opposite the slot where heavier flow material will settle.
In one particular embodiment, the buffer zone around the plurality of transducer elements is an air chamber. In such a case, the method further includes disposing an outer shell around the plurality of transducer elements, and maintaining the air chamber buffer zone between the outer shell and the plurality of transducer elements with standoffs. The outer shell has an internal surface, and the method may further include coating the internal surface with an acoustic reflecting material. In another particular embodiment, providing the buffer zone around the plurality of transducer elements includes disposing a material (e.g., potting material) having an acoustic impedance that inhibits outward projection of acoustic energy around the plurality of transducer elements.
The features and advantages described herein are not all-inclusive and, in particular, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the drawings, specification, and claims. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes, and not to limit the scope of the inventive subject matter.